Background: This study aimed to examine the effect of sodium butyrate on severe acute pancreatitis-related gut barrier injury in a rat model and explore its mechanism. Methods: Male rats randomly fell into 3 groups, that is, the control, the severe acute pancreatitis group, and the severe acute pancreatitis+butyrate group. Rats in the control group received sham operation, while rats in the severe acute pancreatitis group and severe acute pancreatitis+butyrate group received severe acute pancreatitis induction by intraductal infusion of 4% sodium taurocholate. After that, rats in the severe acute pancreatitis+butyrate group were fed with sodium butyrate solution with free access. Intestinal barrier injury was measured based on the expression of tight junction proteins by reverse transcription polymerase chain reaction, Western blotting assay as well as immunohistochemical staining. The variation of Treg cells was measured by reverse transcription polymerase chain reaction, Western blotting assay, immunohistochemical staining, and flow cytometry analysis. Results: Compared to rats in the control, rats in the severe acute pancreatitis group showed significantly higher pathohistological scores (P < .001) in the intestine, as well as decreased expression of occludin and ZO-1. While, rats in the severe acute pancreatitis+butyrate group showed mitigated histologic lesions (P < .05) and increased expressions of occludin and ZO-1. In addition, rats in the severe acute pancreatitis group showed the obvious reduction in the expressions of Foxp3 and GPR109a and the decreased percentage of Treg cells in the intestine (P < .001) compared to rats in the control. However, rats in the severe acute pancreatitis+butyrate group showed markedly increased expressions of Foxp3 and GPR109a and the upregulated percentage of Treg cells (P < .01). Conclusion: Butyrate could significantly mitigate the intestinal injury induced by severe acute pancreatitis, probably by inducing the differentiation of Treg cells. Cite this article as: Xiao S, Jing S, Jiakui S, et al. Butyrate ameliorates intestinal epithelial barrier injury via enhancing Foxp3+ regulatory T-cell function in severe acute pancreatitis model. Turk J Gastroenterol. 2022;33(8):710-719.

Triboelectric nanogenerators were fabricated using organic semiconductor CuPc. With 10 wt% iodine doping, the devices showed an excellent performance with a voltage output of 300 V, a current density of 110 mA m⁻², and a power density of 8.68 W m⁻².

A multilayer structure based on Dirac semimetals is investigated, where long-range surface plasmon resonance (LRSPR) of a dielectric layer/Dirac semimetal/dielectric layer are coupled with surface plasmon polaritons (SPPs) on graphene to substantially improve the Goos–Hänchen (GH) shift of Dirac semimetals in the mid-infrared band. This has important implications for the study of mid-infrared sensors. We studied the reflection coefficient and phase of this multilayer structure using a generalized transport matrix. We established that subtle changes in the refractive index of the sensing medium and the Fermi energy of the Dirac semimetal significantly affected the GH shift. Our numerical simulations show that the sensitivity of the coupling structure is more than $2.7\times {10}^7 \lambda /RIU$, which can be used as a potential new sensor application. The novelty of this work is the design of a tunable, highly sensitive, and simple structured mid-infrared sensor that takes advantage of the excellent properties of Dirac semimetals.